Evaluation of the Shear Bond Strength and Adhesive Remnant Index in Debonding of Stainless Steel Brackets Assisted with Nd:YAG Laser Irradiation

Objectives: The purpose was to compare shear bond strength (SBS), pulp temperature, and adhesive remnant index (ARI) in debonding of stainless steel brackets from enamel surface using neodymium-doped yttrium aluminum garnet (Nd:YAG) laser versus the conventional debonding method. Materials and Methods: Forty-eight extracted premolars were bonded to stainless steel brackets. The samples were divided into three experimental groups and one control group. In the first three groups, Nd:YAG laser was used for debonding with the power of 1, 1.5, and 2 W, respectively, for 10 seconds. The SBS and ARI of the samples were assessed. Pulp temperature was recorded before and after irradiation. Two samples from each group were used for determining enamel morphology after debonding using scanning electron microscopy (SEM). Results: The mean SBS in the groups was 33.05, 28.69, 24.37, and 31.53 MPa, respectively, with no statistically significant differences (P=0.205). Significant differences in post-irradiation temperature were noted among the lased groups (P=0.000). Debonding mainly occurred at the adhesive-enamel interface in the 1-W laser and control groups and at the bracket-adhesive interface in the 1.5-W and 2-W laser groups. Enamel structure was amorphous and irregular following laser irradiation. Conclusions: Based on the results of this study, the use of Nd:YAG laser could not significantly affect the SBS. Therefore, this laser would not be suitable for debonding of metal brackets. The use of a 2-W laser could significantly raise the pulpal temperature. Nd:YAG laser renders a more heterogeneous enamel morphology compared to conventional debonding methods.

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Comparative Evaluation of the Shear Bond Strength and Debonding Properties of a Conventional Composite and Flowable Composites used for Orthodontic Bracket Bonding

World Journal of Dentistry ◽

10.5005/jp-journals-10015-1195 ◽

2013 ◽

Vol 4 (1) ◽

pp. 6-16 ◽

Cited By ~ 1

Author(s):

BM Shivalinga ◽

S Pradeep ◽

Ravi Shanthraj ◽

H Jyothi Kiran

Keyword(s):

Stainless Steel ◽

Bond Strength ◽

Comparative Evaluation ◽

Shear Bond Strength ◽

Orthodontic Bracket ◽

Group Iii ◽

Flowable Composite ◽

Group I ◽

Adhesive Remnant Index ◽

Flowable Composites

ABSTRACT Aim To evaluate and compare shear bond strength (SBS) and debonding characters of the Transbond XT (BisGMA-based composite), Esthet-X flow (flowable composite), Filtek Z-350 (flowable composite). Materials and methods A total of 90 human premolars were divided into group I, Transbond XT (n = 30); group II, Esthet-X flow (n = 30) and group III, Filtek Z-350 (n = 30), the preadjusted edgewise stainless steel premolar brackets were bonded to evaluate the shear bond and debonding properties. Results The results of the statistical analysis comparing the three groups indicated no statistically significant differences between the groups. In general, the SBS with groups I and III exhibited similar bond strength with 11.58 ± 1.3 MPa and 11.07 ± 1.0 MPa respectively. Groups III exhibited least bond strength of 10.7 ± 2 MPa. In modified adhesive remnant index (ARI) the majority of bond failures occurred at enamel-adhesive interface or cohesive type failure in all the three groups. Groups II and III showed increased frequency of score 2, 4 and 5 compared to group I which showed increased frequency of score 0 and 1. Conclusion When considering the SBS and ARI scores obtained, flowable composites can be effectively applied to orthodontic bracket bonding. How to cite this article Pradeep S, Shanthraj R, Kiran HJ, Shivalinga BM. Comparative Evaluation of the Shear Bond Strength and Debonding Properties of a Conventional Composite and Flowable Composites used for Orthodontic Bracket Bonding. World J Dent 2013;4(1):6-16.

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Reinforcement of bond strength of self-etching orthodontic adhesive

The Angle Orthodontist ◽

10.2319/012011-39.1 ◽

2011 ◽

Vol 82 (1) ◽

pp. 30-35

Author(s):

Shinya Horiuchi ◽

Shingo Kuroda ◽

Masahiro Hiasa ◽

Toshiyuki Suge ◽

Seitaro Saku ◽

...

Keyword(s):

Citric Acid ◽

Phosphoric Acid ◽

Bond Strength ◽

Polyacrylic Acid ◽

Shear Bond Strength ◽

Adhesive System ◽

Control Group ◽

Bonding System ◽

Adhesive Remnant Index ◽

Debonding Process

Abstract Objective: To determine the reinforcement of bond strength of a self-etching system by applying a pretreatment agent. Materials and Methods: Sixty extracted human premolars were used in this study. The enamel surfaces were treated with four pretreatment agents—phosphoric acid, polyacrylic acid, citric acid, and ammonium hexafluorosilicate (SiF)—and were examined under a scanning electron microscope. Afterward, orthodontic brackets were bonded with a self-etching adhesive system (n = 10 for each agent), and shear bond strength was measured through a debonding process. The adhesive remnant index (ARI) was also assessed. Results: Enamel surfaces treated with polyacrylic acid seemed almost the same as intact enamel. Treatment with SiF induced slight shallow depressions compared with the intact enamel. On the other hand, enamel surfaces treated with citric acid and phosphoric acid showed severe etching patterns. All pretreatments increased the bond strength, but SiF-treated specimens revealed the greatest strength (12.201 ± 1.048 MPa), followed by polyacrylic acid (12.030 ± 2.103 MPa). The control group with no pretreatment showed the least strength (9.078 ± 1.678 MPa). All pretreatments increased ARI score compared with the control group. Conclusions: Surface conditioning before bracket adhesion could reinforce the bond strength of the self-etching adhesive system, resulting in a more reliable bonding system.

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Etching Enamel for Orthodontics with an Erbium, Chromium:Yttrium-Scandium-Gallium-Garnet Laser System

The Angle Orthodontist ◽

10.2319/120605-426r.1 ◽

2007 ◽

Vol 77 (1) ◽

pp. 117-124 ◽

Cited By ~ 47

Author(s):

Güvenç Basaran ◽

Törün Özer ◽

Nükhet Berk ◽

Orhan Hamamcı

Keyword(s):

Bond Strength ◽

Laser Irradiation ◽

Shear Bond Strength ◽

Laser System ◽

Surface Characteristics ◽

Enamel Surface ◽

Acid Etching ◽

Adhesive Remnant Index ◽

Significant Difference ◽

Power Outputs

Abstract Objective: To test the shear bond strength, surface characteristics, and fracture mode of brackets that are bonded to enamel etched with an erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser operated at different power outputs: 0.5 W, 1 W, and 2 W. Materials and Methods: Human premolars that had been extracted for orthodontic purposes were used. Enamel was etched with an Er,Cr:YSGG laser system operated at one of three power outputs or with orthophosphoric acid. Results: The shear bond strength associated with the 0.5-W laser irradiation was significantly less than the strengths obtained with the other irradiations. Both the 1-W and 2-W laser irradiations were capable of etching enamel in the same manner. This finding was confirmed by scanning electron microscopy examination. The evaluation of adhesive-remnant-index scores demonstrated no statistically significant difference in bond failure site among the groups, except for the 0.5-W laser–etched group. Generally, more adhesive was left on the enamel surface with laser irradiation than with acid etching. Conclusion: The mean shear bond strength and enamel surface etching obtained with an Er,Cr: YSGG laser (operated at 1 W or 2 W for 15 seconds) is comparable to that obtained with acid etching.

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Effect of Nd:YAG Laser Irradiation Pretreatment on the Long-Term Bond Strength of Etch-and-Rinse Adhesive to Dentin

Operative Dentistry ◽

10.2341/15-268-l ◽

2017 ◽

Vol 42 (1) ◽

pp. 62-72 ◽

Cited By ~ 9

Author(s):

J Gan ◽

S Liu ◽

L Zhou ◽

Y Wang ◽

J Guo ◽

...

Keyword(s):

Bond Strength ◽

Laser Irradiation ◽

Nd:Yag Laser ◽

Knoop Hardness ◽

Control Group ◽

In Vitro Test ◽

Dentin Surface ◽

Etch And Rinse ◽

Significant Difference

SUMMARY Purpose: To investigate the effect of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser irradiation pretreatment on the long-term bond strength of an etch-and-rinse adhesive to dentin. Methods: Fifty molars were sectioned parallel to the occlusal plane and randomly divided into two groups (n=25 per group): control group (no treatment) and laser group (dentin surfaces were treated with Nd:YAG laser at a setting of 100 mJ/10 Hz). Afterward, resin was bonded to the dentin surface using a two-step etch-and-rinse adhesive (Adper SingleBond 2), and then 150 beams of each group were produced. Each group was divided into three subgroups (n=50 each group): 24 hours of water storage, thermocycling, and NaOCl storage. The microtensile bond strength (MTBS), failure modes, nanoleakage expression, and Masson's trichrome staining were evaluated. An additional 20 molars were sectioned to obtain 2-mm-thick flat dentin slices. These slices were randomly divided into control and laser-treated groups as mentioned previously. Then slices of each group were examined by scanning electron microscopy, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and the Knoop hardness test. Results: The results of ATR-FTIR and Masson's trichrome verified that laser irradiation partly removed collagen fibers from the dentin surface; however, no significant difference was found in the Knoop hardness (p>0.05). The XRD result showed similar crystalline structure regardless of laser pretreatment. There is no significant difference in short-term MTBS between control and laser-treated groups (p>0.05); however, long-term MTBS differed between the groups (p>0.05). Furthermore, the laser-treated group showed less silver deposition than the control group after aging (p<0.05). Conclusion: Pretreatment by Nd:YAG laser irradiation appeared to have a positive effect on the adhesive-dentin bonding in vitro test, and the bonding effectiveness could be preserved after aging.

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Effects of Different Laser Treatments on Some Properties of the Zirconia-Porcelain Interface

Journal of lasers in medical sciences ◽

10.34172/jlms.2021.02 ◽

2021 ◽

Vol 12 ◽

pp. e2-e2

Author(s):

Abdulsatar M Abdulsatar ◽

Basima M A Hussein ◽

Ali M Mahmood

Keyword(s):

Surface Roughness ◽

Bond Strength ◽

Surface Treatment ◽

Co2 Laser ◽

Nd:Yag Laser ◽

Light Microscope ◽

Shear Bond Strength ◽

Control Group ◽

Fractional Co2 Laser ◽

Laser Treatments

Introduction: This study was performed to compare the effect of Fractional CO2 laser or Q switched Nd:YAG laser of surface treatment on the shear bond strength of zirconia-porcelain interface. Methods: Fractional CO2 laser at 30 W, 2 ms, time interval 1 ms, distance between spots 0.3 mm, and number of scans is (4) or Q switched Nd:YAG laser at 30 J/mm2 and 10 Hz were used to assess the shear bond strength of zirconia to porcelain. Pre-sintered zirconia specimens were divided into three groups (n = 10) according to the surface treatment technique used: (a) untreated (Control) group; (b) CO2 group; (c) Nd:YAG group. All samples were then sintered and veneered with porcelain according to the manufacturer’s instructions. Surface morphology was examined using a light microscope, the surface roughness test was done by the atomic force microscope (AFM), and the shear bond strength (SBS) test was done by a universal testing machine. After debonding following shear bond test, zirconia surfaces were examined under a light microscope to determine their fracture mode. Results: The Results of this study showed that the lowest SBS was recorded in the control group, and the highest SBS recorded in the Fractional CO2 group, followed by the Q switched Nd:YAG laser group, as well as an increase in surface roughness and change in the morphology and mode of failure in the experimental groups . Conclusion: This study shows that Fractional CO2 laser and Q switched Nd:YAG laser treatments significantly increase the bond strength than untreated zirconia .

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The Effect of Different Bracket Base Cleaning Method on Shear Bond Strength of Rebonded Brackets

The Journal of Contemporary Dental Practice ◽

10.5005/jp-journals-10024-1417 ◽

2013 ◽

Vol 14 (5) ◽

pp. 866-870 ◽

Cited By ~ 1

Author(s):

Emad F Al Maaitah ◽

Sawsan Alomari ◽

Elham S Abu Alhaija ◽

Ahmed AM Saf

Keyword(s):

Bond Strength ◽

Failure Mode ◽

Shear Bond Strength ◽

Control Group ◽

Slow Speed ◽

Cleaning Method ◽

Adhesive Remnant Index ◽

Random Samples ◽

Significant Difference ◽

Bracket Base

ABSTRACT Aim To assess the effect of different bracket base conditioning method on shear bond strength (SBS) of rebonded brackets. Materials and methods Eighty brackets were bonded to freshly extracted premolar teeth using light cured composite adhesive. SBS was measured for 20 random samples as control group (G1). After debonding, 60 debonded brackets were allocated randomly into three groups of bracket base conditioning methods to remove the remaining adhesives. G2: bracket base cleaned with slow speed round carbide bur (CB), G3: cleaned with ultrasonic scaler (US), G4: cleaned with sandblasting (SB). After that, brackets were rebonded in the same manner as first bonding and SBS was measured. Modified adhesive remnant index (ARI) was recorded for all groups. Results SBS for new brackets was 11.95 MPa followed by 11.65 MPa for G2, 11.56 MPa for G4 and 11.04 MPa for G3 group. There were no statistically significant differences between all groups (p = 0.946). In all groups, failure mode showed that the majority of adhesive composite remained on the bracket base with ARI of 4. There was no statistically significant difference between all groups in ARI (p = 0.584). Conclusion In-office methods; slow speed CB and US are effective, quick and cheap methods for bracket base cleaning for rebonding. How to cite this article Al Maaitah EF, Alomari S, Alhaija ESA, Safi AAM. The Effect of Different Bracket Base Cleaning Method on Shear Bond Strength of Rebonded Brackets. J Contemp Dent Pract 2013;14(5):866-870.

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Effect of CPP-ACP paste with and without CO2 laser irradiation on demineralized enamel microhardness and bracket shear bond strength

Dental Press Journal of Orthodontics ◽

10.1590/2177-6709.22.4.053-060.oar ◽

2017 ◽

Vol 22 (4) ◽

pp. 53-60 ◽

Cited By ~ 5

Author(s):

Nasrin Farhadian ◽

Loghman Rezaei-Soufi ◽

Seyed Farzad Jamalian ◽

Maryam Farhadian ◽

Shahrzad Tamasoki ◽

...

Keyword(s):

Bond Strength ◽

Laser Irradiation ◽

Co2 Laser ◽

Shear Bond Strength ◽

In Vitro Study ◽

Enamel Surface ◽

Control Group ◽

Demineralized Enamel ◽

Group 2

ABSTRACT Introduction: Many patients seeking orthodontic treatment already have incipient enamel lesions and should be placed under preventive treatments. The aim of this in vitro study was to evaluate the effect of CPP-ACP paste and CO2 laser irradiation on demineralized enamel microhardness and shear bond strength of orthodontic brackets. Methods: Eighty caries-free human premolars were subjected to a demineralization challenge using Streptococcus mutans. After demineralization, the samples were randomly divided into five equal experimental groups: Group 1 (control), the brackets were bonded without any surface treatment; Group 2, the enamel surfaces were treated with CPP-ACP paste for 4 minutes before bonding; Group 3, the teeth were irradiated with CO2 laser beams at a wavelength of 10.6 µm for 20 seconds. The samples in Groups 4 and 5 were treated with CO2 laser either before or through CPP-ACP application. SEM photomicrographs of a tooth from each group were taken to observe the enamel surface. The brackets were bonded to the buccal enamel using a conventional method. Shear bond strength of brackets and ARI scores were measured. Vickers microhardness was measured on the non-bonded enamel surface. Data were analyzed with ANOVA and Tukey test at the p< 0.05 level. Results: The mean shear bond strength and microhardness of the laser group were higher than those in the control group and this difference was statistically significant (p< 0.05). All groups showed a higher percentage of ARI score 4. Conclusion: CO2 laser at a wavelength of 10.6 µm significantly increased demineralized enamel microhardness and enhanced bonding to demineralized enamel.

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Comparison between Shear Bond Strength of Er:YAG and Er,Cr:YSGG Lasers-Assisted Dentinal Adhesion of Self-Adhering Resin Composite: An Ex Vivo Study

Dentistry Journal ◽

10.3390/dj8030066 ◽

2020 ◽

Vol 8 (3) ◽

pp. 66

Author(s):

Paul Nahas ◽

Samir Nammour ◽

Elie Gerges ◽

Toni Zeinoun

Keyword(s):

Bond Strength ◽

Laser Irradiation ◽

Shear Bond Strength ◽

Resin Composite ◽

Control Group ◽

Tooth Structure ◽

Resin Infiltration ◽

Significant Difference ◽

Group 2 ◽

Group 1

(1) Background: Bonding composite to tooth structure is still evolving with a substitute for phosphoric acid being the main challenge. Lately, a self-adhering composite (SAC) was developed, promising to simplify bonding to tooth structure. Unfortunately, retention especially to dentin, was not as good as the gold standard three steps bonding system. During the last 2 decades, lasers were used to enhance shear bond strength of composite to tooth structure. However, the literature provided limited information regarding laser efficiency in the immediate, as well as the long term, adhesion success of SACs to dentin. The purpose of our study was to define the optimal irradiation conditions to improve the adhesion of self-adhering flowable resin composite to dentin exposed to Er:YAG and Er,Cr:YSGG laser irradiation. (2) Methods: Seventy-two freshly extracted human third molars, prepared to have flat dentinal surfaces, were randomly divided into three groups (n = 24) including a control group (Group 1) in which dentin was left without laser irradiation. The other two groups (Group 2 and 3) received standardized irradiation at a speed of 1 mm/second with Er:YAG (60 mJ; SSP mode = 50 μs; 10 Hz; fluency of 9.4 J/cm2; beam diameter: 0.9 mm; air 6 mL/min; and water 4 mL/min), and Er,Cr:YSGG: 1.5 W; fluency of 17.8 J/cm2; turbo handpiece with MX5 short insert; 20 Hz under air/water spray (65% air, 55% water). Self-adhering flowable resin was applied to dentin in all groups. Half of the specimens were stored in water for 24 h while the other half underwent 3000 thermal cycles. Later, all specimens received a shear bond strength test. Fracture observation was done first under a stereomicroscope then by using a scanning electron microscope. (3) Results: The mean values of shear bond strength for both laser-treated dentin groups (Er:YAG laser: 13.10 ± 1.291, and Er,Cr:YSGG: 14.04 ± 5.233) were higher than in the control group 1 (8.355 ± 2.297) before thermocycling. After thermocycling, shear bond strength decreased in all groups as follows: 10.03 ± 1.503, 10.53 ± 2.631, and 02.75 ± 1.583 for Er:YAG, Er,Cr:YSGG, and nonirradiated dentin, respectively. Shear bond strength values showed a significant difference between the control group (Group 1) and both lasers groups (Group 2 and 3). Statistical analysis of stereomicroscope observation revealed no significant difference between laser irradiation and failure mode (p < 0.136). SEM observation of the dentin surface in both laser-irradiated groups showed opened tubules, absence of smear layer as well as an increase of resin infiltration into dentinal tubules. (4) Conclusion: Er:YAG and Er,Cr:YSGG lasers enhance self-adhering flowable resin shear bond strength values and improve its longevity by eliminating the smear layer, opening dentinal tubules and increasing resin infiltration into the microstructure.

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Effect of two erosive protocols using acidic beverages on the shear bond strength of orthodontic brackets to bovine enamel

Dental Press Journal of Orthodontics ◽

10.1590/2177-6709.23.6.064-072.oar ◽

2018 ◽

Vol 23 (6) ◽

pp. 64-72

Author(s):

Catielma Nascimento Santos ◽

Felipe de Souza Matos ◽

Sigmar de Mello Rode ◽

Paulo Francisco Cesar ◽

Flávia Pardo Salata Nahsan ◽

...

Keyword(s):

Bond Strength ◽

Shear Bond Strength ◽

Artificial Saliva ◽

Control Group ◽

Lime Juice ◽

Adhesive Remnant Index ◽

Significant Difference ◽

Microhardness Testing ◽

Bovine Enamel

Abstract Objective: To assess the short-term effect of two in vitro erosive challenge protocols on the bond strength of metal orthodontic brackets on bovine enamel. Methods: Sixty bovine incisors were selected and randomly divided into six groups: AS7 (artificial saliva - 7 days, Control Group); CC7 (Coca-Cola™ - 7 days); LJ7 (lime juice - 7 days); AS30 (artificial saliva - 30 days, Control Group); CC30 (Coca-Cola™ - 30 days); LJ30 (lime juice - 30 days). Microhardness testing was performed prior to the erosive challenge to verify the standardization of samples. Immersion was performed 4x/day for five minutes, for either 7 or 30 days. After immersions were concluded, the brackets were bonded and shear bond strength was assessed after 48 hours. The Adhesive Remnant Index (ARI) was also assessed. Data were analyzed by two-way ANOVA, followed by Tukey’s post-hoc and Student’s t test for paired samples, and the Kruskal-Wallis non-parametric test (α = 5%). Results: The mean and standard deviation of microhardness testing of total samples were 281.89 ± 44.51 KHN. There was no statistically significant difference in shear bond strength for the time factor (7 or 30 days; F5.54= 0.105; p = 0.901). However, there was a statistically significant difference for the solution factor (F5.54= 6.671; p = 0.003). These differences occurred among solutions of Saliva x Coca-Cola™ (p = 0.003) and Coca-Cola™ x Lime Juice (p= 0.029). The assessment of the Adhesive Remnant Index showed no significant difference between groups. Conclusions: The immersion time used in the erosion protocols did not affect the bond strength of brackets to teeth. Coca-Cola™ induced significantly higher shear bond strength values than lime juice and artificial saliva. However, the short term effects of 7/30 days in this in vitro study may not be extrapolated for in vivo ones. Clinical studies should be conducted, substantiating the laboratory results.

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